Electron micrographs demonstrating similar numbers of internalized
bacilli after 6 hours co-incubation with
macrophages. A and B. Full cell view demonstrating electron-dense bacilli (arrowheads) within macrophages. C and D. In both cell types, bacilli are contained within a membrane- (black arrowhead) bound phagolysosome (white arrowhead, electron-luscent phagolysosome lumen). E. Enumeration of internalized bacilli demonstrated no significant difference in uptake of M. marinum between Cd36
+/+ and Cd36
-/- macrophages (p = 0.19). Bacilli were counted in a total of 293 macrophages from 3 independent experiments, taking a minimum of 30 random EM fields for each genotype in each experiment.